The invention relates to a soundproofed exhaust duct for a turbine engine. A particular field of application of the invention is that of processing the sound from a gas turbine engine exhaust, in particular for a helicopter.
The progress that has been made in reducing the noise that is generated by the rotation of the rotor blades of a helicopter means that the noise from the turbine driving the blades is becoming a substantial component of the total amount of sound emitted.
It is therefore desirable to reduce noise from the turbine.
To this end, Document EP 1 010 884 proposes providing the walls of a multichannel exhaust nozzle of a helicopter turbine with a sound energy absorbing coating. The coating is relatively thick, given the sound frequencies concerned, thereby giving rise to problems of weight and of bulk.